The TO waypoint should never be dashed if you have a flightplan in the FMGS (which you have). So it seems that this is a glitch in the simulation software.
Sequencing should be as mentioned before, a FROM waypoint leading to the TO waypoint on the desired radial, and your track intercepting in between. Then arm NAV (it should become blue).
The suggestion Mr Ree gives is valid on later FMGS versions but I don't think that's implemented in this simulator, so it's not possible to do.